Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Trees in the Web of Life. | Journal of Biology BloMed Central Minireview T rees in the Web of Life Kristen S Swithers J Peter Gogarten and Gregory P Fournier Address Department of Molecular and Cell Biology University of Connecticut 91 North Eagleville Road Storrs CT 06269-3125 USA. Correspondence Gregory P Fournier. Email g4nier@ Published 13 July 2009 Journal of Biology 2009 8 54 doi jbiol160 The electronic version of this article is the complete one and can be found online at http content 8 6 54 2009 BioMed Central Ltd Abstract Reconstructing the Tree of Life is complicated by extensive horizontal gene transfer between diverse groups of organisms. While numerous conceptual and technical obstacles remain a report in this issue of Journal of Biology from Koonin and colleagues on the largest-scale prokaryotic genomic reconstruction yet attempted shows that such a tree is discernible although its branches cannot be traced. The Tree of Life ToL is a widely used metaphor to describe the history of life on Earth. While Darwin argued that the Coral of Life may be a more apt description since only the surface remains alive supported by the dead generations beneath it relationships between organisms based on shared characters are best organized using the schematic representation of a tree. Use of molecular markers in particular small-subunit ribosomal RNA have allowed this metaphor to be extended to microorganisms however this has also presented unique challenges for notions of phylogeny and evolution. One of the most significant challenges is the impact of horizontal gene transfer which causes genes that coexist in a genome to have different molecular phylogenies 1 . Despite these challenges the increasing ease with which genomes can be sequenced has reinvigorated attempts to use genomic information to reconstruct the ToL. Combining datasets supertree and supermatrix methods All microbial individuals arise as the result of a fission of a parent individual. Therefore a .
